reclassarg — 用于输入 ST_Reclass 函数的复合类型，用于定义重分类操作的行为。
用于输入 ST_Reclass 函数的复合类型，用于定义重分类操作的行为。
| Field | Type | Description |
|---|---|---|
nband
|
integer | 要重新分类的波段的波段号。 |
reclassexpr
|
text | Comma-delimited range:map_range mappings that define how old band values map to new band values. |
pixeltype
|
text | One of defined pixel types as described in ST_BandPixelType. |
nodataval
|
double precision | 视为无数据的值。 对于支持透明度的图像输出，这些将为空白。 |
The reclassexpr range delimiters mean: ( greater than, ) less than, ] less than or equal, and [ greater than or equal.
[a-b] means a <= x <= b.
(a-b] means a < x <= b.
[a-b) means a <= x < b.
(a-b) means a < x < b.
Opening-parenthesis notation is optional, so a-b means the same as (a-b).
Reclassify band 2 as an 8BUI where 255 is nodata value.
SELECT ROW(2, '0-100:1-10, 101-500:11-150,501 - 10000: 151-254', '8BUI', 255)::reclassarg;
Reclassify band 1 as an 1BB and no nodata value defined.
SELECT ROW(1, '0-100]:0, (100-255:1', '1BB', NULL)::reclassarg;